| Carol Stream to Oerlinghausen | 4,272.69 mi (6,876.24 km) |
| Carol Stream to Oestrich-Winkel | 4,323.06 mi (6,957.29 km) |
| Carol Stream to Offenburg | 4,379.56 mi (7,048.22 km) |
| Carol Stream to Oftersheim | 4,368.99 mi (7,031.20 km) |
| Carol Stream to Ohrdruf | 4,390.50 mi (7,065.83 km) |
| Carol Stream to Ohringen | 4,409.67 mi (7,096.68 km) |
| Carol Stream to Olbernhau | 4,489.43 mi (7,225.03 km) |
| Carol Stream to Olching | 4,517.23 mi (7,269.78 km) |
| Carol Stream to Oldenburg | 4,212.79 mi (6,779.83 km) |
| Carol Stream to Oldenburg in Holstein | 4,261.22 mi (6,857.78 km) |
| Carol Stream to Olfen | 4,235.95 mi (6,817.10 km) |
| Carol Stream to Olpe | 4,278.41 mi (6,885.43 km) |
| Carol Stream to Olsberg | 4,289.41 mi (6,903.14 km) |
| Carol Stream to Oranienburg | 4,401.35 mi (7,083.28 km) |
| Carol Stream to Ortenberg | 4,348.22 mi (6,997.78 km) |
